1. This produet is composed of components, so please use it carefully and do not drop it. 2. When installing this product, if the eccentricity or deviation angle is too large, its service life be shortened. 3. Do not use it in strong impact, vibration, corrosiveness, large magnetic field, high temperature, high humidity and acid-alkaline environment. 4. The error in the number of pulses may be caused by the power ON or OFF. After the power is turned ON, there is a delay time of 0.5S. 5. After the product is fixed, do not pull the cable with a force of more than 29.4N. When there are high-voltage lines or power lines nearby, please cover the cables with conduits. When wiring, be careful not to short-circuit between the terminals, and that the wiring is correct, Wrong wiring damage the internal circuit, It is recommended to conduct insulation protection for the unconnected wires. The shielded wire should be grounded. Do not disassemble the product by yourself. Safety Precautions: 1: The encoder and the shaft should not be rigidly connected, use elastie connectors, the photoelectrie encoder is a high- sensor, and it is strictly forbidden to knock during installation. 2: Please do not wind the eneoder output line and power line together or output in the same slot. and do not place it near the switchboard. 3: Wrong wiring burn out the internal circuit, When wiring, please connect according to the encoder label,and turn it on after checking. Colour:As Shown Material:Metal Package Contents: 4 x Rotary Incremental Encoder 4 set x screw Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.